On Wednesday, the company announced that it adjusted its number of shares outstanding, which gave investors the per-share level to hit the milestone.

This makes Apple the first U.S. company to reach a $1 trillion market capitalization. PetroChina reached a $1 trillion market capitalization briefly in 2007. PetroChina is backed by the Chinese government.

The momentum continued for Apple on Thursday, following the company’s latest quarterly earnings reported on Tuesday.

After the closing bell Tuesday, the tech giant reported that, despite slow-growing demand for the iPhone, that the company benefited from higher prices of its flagship device and that its fiscal third-quarter profit jumped 32% to $11.52 billion. On a per-share basis, earnings hit $2.34 to beat Wall Street’s estimate of $2.18.

Amazon is approaching a $1 trillion market cap. Assuming 484 million shares outstanding, as indicated in Amazon’s second-quarter financial statements. With a share price of $1,810, this puts Amazon’s market capitalization at about $871 billion.